SBEM Assessment Services

SBEM assessment is the mandatory compliance route for non-domestic buildings under Part L of the Building Regulations. Whether you need the design stage SBEM for building control or the as-built assessment to obtain your completion certificate and EPC, Build Energy’s accredited assessors manage the process from initial specification through to submission. For a detailed explanation of the SBEM methodology itself, see our guide to what SBEM calculations are.

Build Energy provides a complete SBEM assessment service covering both stages required by the Building Regulations.

Build Energy submits the Design Stage SBEM (Part L2) to building control before construction begins. It measures the building’s Carbon Dioxide Emission Rate against a Target CO₂ Emission Rate (TER). The TER comes from a notional reference building of equivalent size and shape. The output is a BRUKL compliance report accepted by building control authorities across England and Wales.

Build Energy produces the As-Built SBEM on completion of the project. This reflects the building as constructed, incorporating any specification changes made during construction. You need this submission before building control issues your completion certificate and non-domestic EPC.

In some cases, for buildings with complex or bespoke HVAC systems, Build Energy may recommend Dynamic Simulation Modelling (DSM) as an alternative compliance route. DSM uses fewer default values and typically achieves a more efficient rating, which can reduce over-specification and deliver real cost savings on plant sizing.

Part L2B applies to existing non-domestic buildings undergoing significant extension or material change of use. The compliance targets and allowable approaches differ from new-build requirements under Part L2A. However, SBEM calculations are still required at both design stage and practical completion.

Common scenarios requiring Part L2B SBEM include warehouse extensions, office fit-outs involving a change of use, and retail or hospitality conversions. Build Energy handles Part L2B assessments across all building types. We work alongside architects and contractors to identify the most practical route to compliance from early in the design process.

Build Energy’s assessors are experienced across all major non-domestic building types: offices, retail, industrial,

healthcare, education, leisure and public-sector. We work with architects, developers, main contractors and M&E engineers throughout the design and construction process.

To begin an SBEM assessment, we typically need architectural drawings and a construction specification. This should cover U-values, window details, and heating, ventilation and lighting systems. A Stage 2 design is usually sufficient to start. We track any specification changes during the project and update the calculation accordingly, so there are no surprises at as-built stage.

SBEM calculations sit alongside other compliance requirements on commercial projects. Most schemes require a planning-stage Energy Statement. For residential projects, see SAP calculations. Return to the Part L SBEM Calculations hub.

What does SBEM calculate?

SBEM calculates the Carbon Dioxide Emission Rate (BER) of a proposed building and compares it against a Target CO₂ Emission Rate (TER) derived from a notional building of the same size and shape. The building complies with Part L2A if the BER does not exceed the TER.

What information does Build Energy need to produce SBEM calculations?

Build Energy typically needs architectural drawings (floor plans, elevations, sections), the construction specification (wall, roof and floor U-values), window specifications, details of the heating, cooling and ventilation systems, lighting specifications, and any renewable energy measures. A Stage 2 specification is sufficient to begin.

Can SBEM be used for all non-domestic buildings?

SBEM is suitable for most non-domestic buildings. However, for buildings with complex or bespoke HVAC systems – such as large mixed-use developments or highly serviced commercial buildings – Dynamic Simulation Modelling (DSM) may be required or may be more appropriate as the compliance method.

What is the difference between Part L2A and Part L2B?

Part L2A applies to new non-domestic buildings; Part L2B applies to extensions and material changes of use in existing non-domestic buildings. Both require SBEM calculations, but the compliance targets and allowable approaches differ between them.

Does Build Energy provide the Design Stage and As-Built SBEM?

Yes. Build Energy handles both the Design Stage SBEM submission (required before construction) and the As-Built SBEM (required on completion). We track any specification changes during the project and update the calculation accordingly.